insulation and thermal barriers

GENERAL INFORMATION

Insulation in agricultural buildings may increase the fire risk and fire spread. All plastic insulation materials are considered combustible, producing toxic smoke and gases, and may contribute to the spread and intensity of the fire. The use of these materials, left exposed on the interior of buildings, is not acceptable for fire insurance underwriting purposes. Choose an insulation product that is fire-resistant and suitable for an adverse interior environment. Insulation adjacent to heaters, electrical equipment, and welding operations must be protected with thermal barriers.

POLYURETHANE AND POLYSTYRENE FOAM INSULATION

• Polyurethane Spray Applied (Thermal Barrier Required) - This product is mixed and spray-applied on walls and ceilings at varying thicknesses.
• Polyurethane/Polystyrene Rigid Foam Board (Thermal Barrier Required) - A urethane or styrene rigid foam board with or without laminated vinyl, foil, or aluminum facers (also known as blue, gray, yellow, or pink insulation board).
• Polystyrene Bead Board (Thermal Barrier Required) - A molded-bead, cellular-plastic insulation board, white in color and without a facer.
• Polyicynene Expanding Foam Insulation (Thermal Barrier Required) - Polyicynene is applied by spraying liquid components into a wall or cavity. The product will be consumed by flame but will not contribute to fire spread.

APPROVED THERMAL BARRIERS

Most plastic insulation products must be protected with a thermal barrier to meet fire insurance underwriting requirements. The following thermal barriers will protect plastic insulation from igniting and will prevent rapid fire spread if properly installed and maintained. 

Rigid Thermal Barriers

• 1/2-inch cement plaster;
• 1/2-inch fire-retardant treated plywood;
• 1/2-inch type-X fired-rated gypsum board/drywall (5/8-inch type-X gypsum board is required for a one-hour fire wall).

SPRAY APPLIED THERMAL BARRIERS

Contego International and DC315 (Brand Name) are single-component, water-based, acrylic latex coating.  The product may be applied over combustible surfaces such as foam insulation, wood, or plastic interior surfaces. The product may be sprayed, brushed, or roller-applied to a desired thickness per manufactures' specifications.

Comparable products listed as thermal barriers by UL (Underwriters Laboratories), FM (Factory Mutual), or other recognized testing laboratories may be acceptable. Consult with Bray-Gentilly Mutual Insurance.

THERMAL BARRIER vs. IGNITION BARRIER vs. FIRE RETARDANT COATING

Thermal Barrier - A thermal barrier is a thick material applied to the spray foam that slows down the rise of the temperature of the foam during a fire situations to delay or prevent the foams involvement in the fire. The thickness of the thermal barrier allow san escape time of 15 Minutes for occupants.

Ignition Barrier - An ignition barrier is a thin, spray on or brush on coating that prevents the ignition of the product to which its applied from a spark or from direct heat, but does not protect from direct flame over a period of time. Ignition barriers are applied to spray foam in spaces that are rarely accessed by people, such as attics or crawl spaces. 

Fire-Retardant Coating - Intumescent Paints - A brush or spray-on material that is applied to the surface of a building component or object to reduce combustibility or slow the spread of a fire. Fire retardant substances can also be added to combustible materials to make them less combustible. Fire retardant coatings are not approved for application over spray foam insulations. (for example: spray retardant on a Christmas tree to prevent from burning.)